<!DOCTYPE html>
<html>
<head>
<style>
h1 {
display: block;
font-size: 2em;
margin-top: 0.67em;
margin-bottom: 0.67em;
margin-left: 0;
margin-right: 0;
font-weight: bold;
}
</style>
</head>
<body>
<p>An h1 element is displayed like this:</p>
<h1>This is heading 1</h1>
<p>Change the default CSS settings to see the effect.</p>
</body>
</html>